Multicast Source Discovery Protocol (MSDP) is a

Protocol Independent Multicast 400px, Example of a multicast network architecture Protocol-Independent Multicast (PIM) is a family of multicast routing protocols for Internet Protocol (IP) networks that provide one-to-many and many-to-many distribution of data over a LAN, WA ...

(PIM) family

multicast routing protocol Multicast routing is one of the routing protocols in IP networking. CISCO Security Research & Operations- 3 June 201Understanding Unicast Reverse Path Forwarding , Cisco -unicast-reverse-path-forwarding/ref> There are several multicast rout ...

defined by Experimental RFC 3618. Despite becoming the IPv4

de facto standard A ''de facto'' standard is a custom or convention that has achieved a dominant position by public acceptance or market forces (for example, by early entrance to the market). is a Latin phrase (literally "in fact"), here meaning "in practice but ...

for inter-domain multicast, development of the protocol stopped in 2006 and it was decided by the authors not to proceed with making it a proposed standard. MSDP interconnects multiple

IPv4 Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version d ...

PIM Sparse-Mode (PIM-SM) domains which enables PIM-SM to have Rendezvous Point (RP) redundancy and inter-domain multicasting RFC 4611. MSDP uses

TCP TCP may refer to: Science and technology * Transformer coupled plasma * Tool Center Point, see Robot end effector Computing * Transmission Control Protocol, a fundamental Internet standard * Telephony control protocol, a Bluetooth communication s ...

as its transport protocol. Each multicast tree needs to have its own RP. All of the RPs are peers (directly or through other MSDP peers). Messages contain the sender (source) address and the multicast group address (S,G). If an RP on its own domain receives a message, it determines if there are listeners for this group. If listeners exist, it triggers a PIM join into the source domain towards the data source. In a peering relationship, one MSDP peer listens for new TCP connections on the well-known port 639. MSDP is deliberately unspecified for IPv6, for a number of reasons, including that protocols such as Source-Specific Multicast (SSM),

Bi-directional Multicast Bidirectional may refer to: * Bidirectional, a roadway that carries traffic moving in opposite directions * Bi-directional vehicle, a tram or train or any other vehicle that can be controlled from either end and can move forward or backward with e ...

and IPv6 Embedded Rendezvous Points would mean there was less requirement for MSDP.

External links

Multicast BGP Multiprotocol Extensions for BGP (MBGP or MP-BGP), sometimes referred to as Multiprotocol BGP or Multicast BGP and defined in IETF RFC 4760, is an extension to Border Gateway Protocol (BGP) that allows different types of addresses (known as address ...

References

{{compu-network-stub Routing protocols Internet protocols